Dienone-Phenol Tautomerism: The tautomer of 3,5-dipyrrolidinophenol existing in aqueous solution has been shown to be the 2,4-dienone, with the position of equilibrium determined by hydrogen-bonding characteristics of the solvent. NMR: The C-13 nmr characteristics of Dendrobates alkaloids and allenic secoandrostantriones have been investigated. Degradative Studies: A superior method for the characterization of unsaturated lactones by mass spectral means has been developed. BIBLIOGRAPHIC REFERENCES: Highet, R.J., Perold, G.W., and Sokoloski, E.A., Characterization of Spiro-bislactonic Phenolic Metabolics of Proteaceae by Carbon-13 Nuclear Magnetic Resonance," J. Org. Chem., 41: 3860-3862, 1976. Eppley, R.M., Mazzola, E.P., Highet, R.J., and Bailey, W.J., "Structure of Satratoxin H, a Metabolite of Stachybotrys alba. Application of 1H and 13C Nuclear Magnetic Resonance." J. Org. Chem. 42: 440-443, 1977.